Inspired by older thread on Extending Range I have been gathering components for a similar project but haven't advanced much farther than that. I am using a Lifan 139F 2 engine for power, a 24 volt 250 watt brush scooter motor for generator, and a 24 volt to 12 volt DC Golf cart converter for charging the 48 volt 1400 mah Litthium ion battery for my 1000 watt hub motor. The setup that I am currently testing is relatively simple. using standard components and my wall charger. I am curious to learn more about David's auto throttle design, because I wouldn't have a clue how to proceed with that, so I have settled on this simple approach for now. I am planning on mounting the components on a Phatmoto Rover bike that I have recently purchased.
Extend Electric Bike Range by Recharging on Route
- Thread starter Davideo
- Start date
Tony01
Well-Known Member
You might be better off building a hybrid instead. That motor would barely drive a bike by itself, but also running it through two motors and converters, and a battery, will cause the motor to have to run many times more per mile. Whereas with the gas engine directly driving the rear wheel you only lose a few percent.
Sidewinder Jerry
Well-Known Member
When under gas only and/or pedaling and/or going down hill the electric throttle/clutch could be in the off position, a clutching system could disengage the motor from the gearbox. A left side wheel pulley would drive the motor and it'd act like a generator. The controller would reverse the polarity.
When the motor was being used the clutching system would disengage the left side drive pulley and the motor would draw power from the battery to assist the engine. I'm thinking along lines of a duel shaft motor being used to accomplish what I'm talking about.
Hybrid cars operate on a similar system to where the electric motor acts like a generator to put charge back into the battery when it isn't being used to propel the car.
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Thanks for this. Interesting concept! Food for thought, I will need a while to think through the transmission and clutching requirements before I will completely understand how it could be implemented.
Sidewinder Jerry
Well-Known Member
I'm thinking if you use a double shafted motor; on the gearbox side a freewheel could be used to drive the gearbox. On the back side of the motor that shaft would be driven in reverse when the clutch is engaged. I'll draw up the concept for you.
This set up will also allow you to use a shift kit as well.
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Sidewinder Jerry
Well-Known Member
Since the early days of building there's always been those who figure out a way to make something work. Then there are those who take the prototype type and figure out a way to make it look good.
My thoughts were to install a 1000 watt 48 volt hub motor on the front wheel of the Phatmoto Rover and to build a little gas driven generator with those components that can be installed without too much trouble. While I love the lines of the bike I am thinking that with its 80 cc four stroke, it may look a little too ballsy for the other riders on the bike-way.
Sidewinder Jerry
Well-Known Member
I once saw a low rpm generator like what's used in small windmills. You could use a large left side belt pulley to drive it. Then the throttle could switch between battery power and generator power when the electric drive motor only was being used.
If pedal power and/or gravity power and/or gas power was being used generator power could be used to power the electric drive motor.
When the electric drive motor wasn't being used the low rpm generator would put charge back into the battery whenever the bike was moving.
So this means you'd have to use 2 electric motors to accomplish this. The low rpm generator could only charge the battery or provide power to the drive motor when the bike was moving.
The electric drive motor could be either powered from the generator motor or the battery.
indian22
Well-Known Member
Tony you've touched on a relevant point, that being efficiency, and the gas /electric hybrid setup is. It's also practical in everyday use and the wheel hub & gas motor hybrid is simple to install, use and maintain. Setup to regen it also acts as a battery charger while it provides extra power on demand to assist the gas motor. With the 2-cycle engines the electric acts as a starter motor. The hybrid components aren't very expensive for 500watt to 1kw setups. Though if you want a lot of power it's going to cost a lot more, but that's true of straight gas bikes as well.
One of the great advantages of an electric wheel hub type hybrid bicycle is the redundancy of systems to get you where you're going and back. If either the electric or gas motors fail or you run out of gas or drain the battery you've the other motor to get you home...and the pedals work as well, but if you break both chains (highly unlikely but) the front wheel mounted hub motor is still good to go. I can go on but won't.
I've been riding a gas/electric hybrid for a few months now so it's not theoretical with me it's a solid fact. I put 500 miles on mine in one three day trip last Fall & over a thousand miles the first month getting ready for the long trip I took a couple of hundred mile rides.
While I encourage everyone to try new stuff and build what you can imagine, cause it's fun and cool, but keep in mind there's a lot of stuff out there that really works well too.
Have fun!
Rick C.
LR Jerry, where can I find one of these "large side belt Pulleys" so that I can check it out and see what it looks like?
Rick I like your choice for a battery mounting location, I was thinking of the parcel carrier for my project.
indian22
Well-Known Member
Davideo a well mounted rack is an excellent addition to any bike and adds real utility as does a trailer hitch. I use both on my hybrid and my other e-bikes. I can carry thee extra lithium batteries on my hybrid rack two in my leather saddle bags and one on top of the rack. This makes a really long range bike as I can squeeze almost a hundred miles on one tank of fuel and about 40 miles from each of the four battery, packs, if I help with the pedals I can stretch it quite a bit further at 15 to 20 mph. I use the gas motor as the primary power, on the road, but I use the electric motor with pedals inside urban areas that I'm not familiar with because local codes vary.
Rick C.
Rick C.
She is a beauty Rick. Very impressive range figures too, far greater than what I was hoping for.
Sidewinder Jerry
Well-Known Member
Golden Eagle has them and so do many whizzer kit builds.
https://www.bikeengines.com/product-category/parts-accessories/miscellaneous/
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indian22
Well-Known Member
Thanks Davideo. Extended range using hybrid electrics is an outstanding goal and exploring innovative approaches is worthwhile. The point I'm addressing is for those who are searching for a practical "right now solution" to extend their range and all around performance at reasonable cost levels. I'm not trying to stop others from exploring and developing interesting alternatives. Build away and enjoy!
Rick C.
